Method and process arrangement for producing solid product and use

Abstract

The invention relates to a method and a process arrangement for producing a solid product, e.g. biochar, by means of a gasification. Bio-based raw material (1) is gasified for forming a product gas (4) and a solid co-product (5) in a gasifier (2), and a gasification temperature is arranged to temperature of 750 - 850° C. for increasing a yield of the solid co-product. Further, the invention relates to the use of the solid co-product.

1 . A method for producing a solid product by means of a gasification, the method comprising: 
 gasifying bio-based raw material for forming a product gas and a solid co-product; and   arranging a gasification temperature to temperature of 750 - 850° C. for increasing a yield of the solid co-product; and   feeding an oxygen or air 10 - 22 % of stoichiometric amount of oxygen to the gasification to provide a defined temperature during the gasification.   
     
     
         2 . The method according to  claim 1 , whereinthe temperature is 780 - 830° C. during the gasification. 
     
     
         3 - 4 . (canceled) 
     
     
         5 . The method according to  claim 1 , wherein at least a part of the solid co-product is recirculated back to the gasification. 
     
     
         6 . The method according to  claim 1 , wherein the yield of the solid co-product is 10 - 20% of the bio-based raw material carbon content. 
     
     
         7 . The method according to  claim 1 , whereinthe product gas is treated by a synthesis process to form a final product. 
     
     
         8 . The method according to  claim 1 , wherein the product gas-(4) has H 2 /CO -ratio which is 1.8 - 2.2. 
     
     
         9 . The method according to  claim 1 , wherein the product gas-(4) has H 2 /CO -ratio which is 2.8 - 3.2. 
     
     
         10 . The method according to  claim 1 , wherein the product gas is filtrated. 
     
     
         11 . A process arrangement for producing a solid product by means of a gasification, wherein the process arrangement comprises:
 at least one gasifier-(2) for gasifying bio-based raw material to form a product gas and a solid co-product;   at least one temperature control device for adjusting a gasification temperature to temperature of 750 - 850° C. in order to increase a yield of the solid co-product such that an oxygen or air is fed 10 - 22 % of stoichiometric amount of oxygen to the gasification to provide a defined temperature during the gasification; and   at least one recovery device for recovering the solid co-product in connection with the gasifier.   
     
     
         12 . The process arrangement according to  claim 11 , wherein the at least one gasifier-(2) is a circulating fluidized-bed (CFB) gasifier or bubbling fluidized-bed (BFB) gasifier. 
     
     
         13 . The process arrangement according to  claim 11 , whereinthe process arrangement comprises at least one recirculating device for recirculating at least a part of the solid co-product back to the at least one gasifier-(2). 
     
     
         14 . The process arrangement according to  claim 11 , whereinthe process arrangement comprises at least one synthesis device for treating the product gas-by a synthesis process to form a final product. 
     
     
         15 . The process arrangement according to  claim 14 , whereinthe process arrangement can comprise at least one reformer in which the product gas is treated after the at least one gasifier-(2) or before the synthesis device. 
     
     
         16 . The process arrangement according to  claim 11 , whereinthe process arrangement comprises at least one filtration unit for filtrating the product gas. 
     
     
         17 . The process arrangement according to  claim 11 , wherein the process arrangement comprises at least one electrolysis unit for forming hydrogen. 
     
     
         18 . A method comprising:
 producing a solid co-product, the producing comprising,
 gasifying bio-based raw material to form a product gas and the solid co-product; 
 arranging a gasification temperature to a temperature of 750 - 850° C. to increase a yield of the solid co-product; 
   feeding an oxygen or air 10 - 22 % of stoichiometric amount of oxygen to the gasification to provide a defined temperature during the gasification;   using the solid co-product as at least one of a soil conditioner, a fuel or raw material in a combustion process, and a coke in an industrial process.   
     
     
         19 . The method according to  claim 18 , wherein the temperature is 780 - 830° C. during the gasification. 
     
     
         20 . The method according to  claim 18 , wherein at least a part of the solid co-product is recirculated back to the gasification.